The greenscape shapes surfing of resource waves in a large migratory herbivore.

The Green Wave Hypothesis posits that herbivore migration manifests in response to waves of spring green-up (i.e. green-wave surfing). Nonetheless, empirical support for the Green Wave Hypothesis is mixed, and a framework for understanding variation in surfing is lacking. In a population of migratory mule deer (Odocoileus hemionus), 31% surfed plant phenology in spring as well as a theoretically perfect surfer, and 98% surfed better than random. Green-wave surfing varied among individuals and was unrelated to age or energetic state. Instead, the greenscape, which we define as the order, rate and duration of green-up along migratory routes, was the primary factor influencing surfing. Our results indicate that migratory routes are more than a link between seasonal ranges, and they provide an important, but often overlooked, foraging habitat. In addition, the spatiotemporal configuration of forage resources that propagate along migratory routes shape animal movement and presumably, energy gains during migration.

[1]  Benjamin M. Bolker,et al.  Linear and generalized linear mixed models , 2015 .

[2]  D. Costa,et al.  Migratory shearwaters integrate oceanic resources across the Pacific Ocean in an endless summer , 2006, Proceedings of the National Academy of Sciences.

[3]  A. Mysterud,et al.  Behavioral buffering of extreme weather events in a high-Arctic herbivore , 2016 .

[4]  K. Burnham,et al.  Comparison of model building and selection strategies , 2010, Journal of Ornithology.

[5]  Pilar López,et al.  When to come out from a refuge: risk- sensitive and state-dependent decisions in an alpine lizard , 1999 .

[6]  David Frank,et al.  Timing and duration of European larch growing season along altitudinal gradients in the Swiss Alps. , 2010, Tree physiology.

[7]  I. Couzin,et al.  Social interactions, information use, and the evolution of collective migration , 2010, Proceedings of the National Academy of Sciences.

[8]  A. Frid,et al.  State-dependent risk-taking by green sea turtles mediates top-down effects of tiger shark intimidation in a marine ecosystem. , 2007, The Journal of animal ecology.

[9]  M. E. Nelson,et al.  Development of migratory behavior in northern white-tailed deer , 1998 .

[10]  I. Hodkinson,et al.  Terrestrial insects along elevation gradients: species and community responses to altitude , 2005, Biological reviews of the Cambridge Philosophical Society.

[11]  Hall Sawyer,et al.  Stopover ecology of a migratory ungulate. , 2011, The Journal of animal ecology.

[12]  I. Gordon,et al.  HERBIVORE PHYSIOLOGICAL STATE AFFECTS FORAGING TRADE-OFF DECISIONS BETWEEN NUTRIENT INTAKE AND PARASITE AVOIDANCE , 2001 .

[13]  R. Bell A grazing ecosystem in the Serengeti , 1971 .

[14]  Mark Harrower,et al.  MapShaper.org: a map generalization Web service , 2006, IEEE Computer Graphics and Applications.

[15]  T. Stephenson,et al.  Timing of seasonal migration in mule deer: effects of climate, plant phenology, and life‐history characteristics , 2011 .

[16]  Atle Mysterud,et al.  A Migratory Northern Ungulate in the Pursuit of Spring: Jumping or Surfing the Green Wave? , 2012, The American Naturalist.

[17]  Alasdair I. Houston,et al.  Risk-sensitive foraging: A review of the theory , 1992 .

[18]  Damaris Zurell,et al.  The challenges of the first migration: movement and behaviour of juvenile vs. adult white storks with insights regarding juvenile mortality. , 2016, The Journal of animal ecology.

[19]  John M. Fryxell,et al.  Opposing Rainfall and Plant Nutritional Gradients Best Explain the Wildebeest Migration in the Serengeti , 2009, The American Naturalist.

[20]  Jonathan B. Armstrong,et al.  Riding the crimson tide: mobile terrestrial consumers track phenological variation in spawning of an anadromous fish , 2013, Biology Letters.

[21]  David R. Anderson,et al.  Model selection and multimodel inference : a practical information-theoretic approach , 2003 .

[22]  N. Bunnefeld,et al.  A model-driven approach to quantify migration patterns: individual, regional and yearly differences. , 2011, The Journal of animal ecology.

[23]  Kent R. Hersey,et al.  Effects of climate and plant phenology on recruitment of moose at the southern extent of their range , 2015, Oecologia.

[24]  K. Parker,et al.  Nutrition integrates environmental responses of ungulates. , 2009 .

[25]  R. Drent,et al.  Balancing the energy budgets of arctic-breeding geese through- out the annual cycle: a progress report , 1978 .

[26]  Devin S Johnson,et al.  Continuous-time correlated random walk model for animal telemetry data. , 2008, Ecology.

[27]  Daniel Fortin,et al.  To follow or not? How animals in fusion-fission societies handle conflicting information during group decision-making. , 2015, Ecology letters.

[28]  Gil Bohrer,et al.  Elephant movement closely tracks precipitation-driven vegetation dynamics in a Kenyan forest-savanna landscape , 2014, Movement ecology.

[29]  L. J. Verme,et al.  Relation of Maternal Age to Fawn-Rearing Success in White-Tailed Deer , 1986 .

[30]  Marco Heurich,et al.  Green wave tracking by large herbivores: an experimental approach. , 2016, Ecology.

[31]  J A Merkle,et al.  A memory-based foraging tactic reveals an adaptive mechanism for restricted space use. , 2014, Ecology letters.

[32]  I. Couzin,et al.  Emergent Sensing of Complex Environments by Mobile Animal Groups , 2013, Science.

[33]  P. Jarman,et al.  The Social Organisation of Antelope in Relation To Their Ecology , 1974 .

[34]  Garrett M. Street,et al.  On the adaptive benefits of mammal migration , 2014 .

[35]  Nathalie Pettorelli,et al.  Importance of climatological downscaling and plant phenology for red deer in heterogeneous landscapes , 2005, Proceedings of the Royal Society B: Biological Sciences.

[36]  John F. Wilmshurst,et al.  PREDICTIVE MODELS OF MOVEMENT BY SERENGETI GRAZERS , 2004 .

[37]  S. Åkesson,et al.  Long-distance migration: evolution and determinants , 2003 .

[38]  John M. Fryxell,et al.  Forage Quality and Aggregation by Large Herbivores , 1991, The American Naturalist.

[39]  W. Porter,et al.  Behavior and nutritional condition buffer a large‐bodied endotherm against direct and indirect effects of climate , 2014 .

[40]  A. Munn,et al.  Assessing the Jarman-Bell Principle: Scaling of intake, digestibility, retention time and gut fill with body mass in mammalian herbivores. , 2013, Comparative biochemistry and physiology. Part A, Molecular & integrative physiology.

[41]  H. Dingle Migration: The Biology of Life on the Move , 1996 .

[42]  T. Stephenson,et al.  Effects of tooth extraction on body condition and reproduction of mule deer , 2003 .

[43]  Jonathan B. Armstrong,et al.  Resource waves: phenological diversity enhances foraging opportunities for mobile consumers. , 2016, Ecology.

[44]  A. Skidmore,et al.  Migratory Herbivorous Waterfowl Track Satellite-Derived Green Wave Index , 2014, PloS one.

[45]  M. Kauffman,et al.  Animal migration amid shifting patterns of phenology and predation: lessons from a Yellowstone elk herd. , 2013, Ecology.

[46]  Robert B O'Hara,et al.  Social Learning of Migratory Performance , 2013, Science.

[47]  D. Grünbaum Schooling as a strategy for taxis in a noisy environment , 1998, Evolutionary Ecology.

[48]  F. Bunnell,et al.  Effects of learning on food selection and searching behaviour of deer , 1989 .

[49]  J. Hopcraft,et al.  Serengeti wildebeest migratory patterns modeled from rainfall and new vegetation growth. , 2006, Ecology.

[50]  Nathalie Pettorelli,et al.  Early onset of vegetation growth vs. rapid green-up: impacts on juvenile mountain ungulates. , 2007, Ecology.

[51]  A. Mysterud,et al.  Plant phenology, migration and geographical variation in body weight of a large herbivore: the effect of a variable topography , 2001 .

[52]  Asynchronous vegetation phenology enhances winter body condition of a large mobile herbivore , 2015, Oecologia.

[53]  William F. Fagan,et al.  Search and navigation in dynamic environments – from individual behaviors to population distributions , 2008 .

[54]  Simon Benhamou,et al.  Spatial memory and animal movement. , 2013, Ecology letters.

[55]  Stopover Habitats of Spring Migrating Surf Scoters in Southeast Alaska , 2011 .

[56]  Ellen O. Aikens,et al.  Large herbivores surf waves of green-up during spring , 2016, Proceedings of the Royal Society B: Biological Sciences.

[57]  S. Albon,et al.  Plant phenology and the benefits of migration in a temperate ungulate , 1992 .

[58]  Zaida Ortega,et al.  Behavioral buffering of global warming in a cold‐adapted lizard , 2016, Ecology and evolution.

[59]  Rick L. Lawrence,et al.  Using NDVI and EVI to Map Spatiotemporal Variation in the Biomass and Quality of Forage for Migratory Elk in the Greater Yellowstone Ecosystem , 2016, Remote. Sens..

[60]  Gil Bohrer,et al.  In search of greener pastures: Using satellite images to predict the effects of environmental change on zebra migration , 2013 .